It has a Yashinon DX 45mm f/1.7 lens.

This was my dad's last camera. My mom gave it to me after
he passed away. It still works although you can't buy batteries
for it any longer. Similar output batteries are available but
the dimensions are different so you have to do a bit of shimming
to make them work. It was marketed around 1973; before "through
the lens" days so it's possible to take a shot with the lens cap on.
Anyone else old enough to have had this experience??? :)